代码

#pragma G++ optimize(2)
#pragma G++ optimize(3)
#pragma G++ optimize("Ofast")
#pragma G++ optimize("inline")
#pragma G++ optimize("-fgcse")
#pragma G++ optimize("-fgcse-lm")
#pragma G++ optimize("-fipa-sra")
#pragma G++ optimize("-ftree-pre")
#pragma G++ optimize("-ftree-vrp")
#pragma G++ optimize("-fpeephole2")
#pragma G++ optimize("-ffast-math")
#pragma G++ optimize("-fsched-spec")
#pragma G++ optimize("unroll-loops")
#pragma G++ optimize("-falign-jumps")
#pragma G++ optimize("-falign-loops")
#pragma G++ optimize("-falign-labels")
#pragma G++ optimize("-fdevirtualize")
#pragma G++ optimize("-fcaller-saves")
#pragma G++ optimize("-fcrossjumping")
#pragma G++ optimize("-fthread-jumps")
#pragma G++ optimize("-funroll-loops")
#pragma G++ optimize("-fwhole-program")
#pragma G++ optimize("-freorder-blocks")
#pragma G++ optimize("-fschedule-insns")
#pragma G++ optimize("inline-functions")
#pragma G++ optimize("-ftree-tail-merge")
#pragma G++ optimize("-fschedule-insns2")
#pragma G++ optimize("-fstrict-aliasing")
#pragma G++ optimize("-fstrict-overflow")
#pragma G++ optimize("-falign-functions")
#pragma G++ optimize("-fcse-skip-blocks")
#pragma G++ optimize("-fcse-follow-jumps")
#pragma G++ optimize("-fsched-interblock")
#pragma G++ optimize("-fpartial-inlining")
#pragma G++ optimize("no-stack-protector")
#pragma G++ optimize("-freorder-functions")
#pragma G++ optimize("-findirect-inlining")
#pragma G++ optimize("-fhoist-adjacent-loads")
#pragma G++ optimize("-frerun-cse-after-loop")
#pragma G++ optimize("inline-small-functions")
#pragma G++ optimize("-finline-small-functions")
#pragma G++ optimize("-ftree-switch-conversion")
#pragma G++ optimize("-foptimize-sibling-calls")
#pragma G++ optimize("-fexpensive-optimizations")
#pragma G++ optimize("-funsafe-loop-optimizations")
#pragma G++ optimize("inline-functions-called-once")
#pragma G++ optimize("-fdelete-null-pointer-checks")
#include<bits/stdc++.h>
#define int long long
using namespace std;
int a[10000010];
int dp[10000010];
int n;
inline void operation1(int x,int y)
{
	a[x]=y;
}
inline int operation2(int l,int r)
{
	memset(dp,0,sizeof(dp));
	int maxn=-0x7f7f7f7f;
	for(int i=l;i<=r;i++)
	{
		if(i<2)
		{
			dp[i]=a[i];
		}
		else
		{
			dp[i]=max(a[i],dp[i-1]+a[i]);
		}
		maxn=max(dp[i],maxn);
	}
	return maxn;
}
inline void write(int x)
{
    if(x<0)
	{
    	putchar('-');
		x=-x;
	}
    if(x>9)
    {
    	write(x/10);
	}
    putchar(x%10+'0');
}
inline int read() 
{
     bool f=false; 
	 int x=0;
     char ch=getchar();
     while(ch<'0'||ch>'9') 
	 {
         if(ch=='-') 
		 {
		 	f=true;
		 }
         ch=getchar();
     }
     while(ch>='0'&&ch<='9') 
	 {
         x=(x<<1)+(x<<3)+ch-'0';
         ch=getchar();
     }
     return f?-x:x;
 }
signed main()
{
	int q;
	n=read();
	q=read();
	for(int i=1;i<=n;i++)
	{
		a[i]=read();
	}
	while(q--)
	{
		int op;
		op=read();
		if(op==2)
		{
			int x,y;
			x=read();
			y=read();
			operation1(x,y);
		 } 
		if(op==1)
		{
			int l,r;
			l=read();
			r=read();
			if(l>r)
			{
				swap(l,r);
			}
			write(operation2(l,r));
			putchar('\n');
		}
	}
	return 0;
}

18pts